FAMILY 11. COLUMELLATA. 25] 
borate sculpture, or for their vivid display of colours, were separated by 
Lamarck from the Linnean Volute ; it must, however, be remembered 
that they were designated by the common appellatives of ‘‘ the Bishop’s 
Mitre,” ‘‘the Pope’s Mitre,” “ the Cardinal’s Mitre,” and so forth, by 
Klein, Rumphius, and many of the first naturalists after the revival of 
letters. They exhibit a much smaller average size, and are especially 
marked by a turriculated or fusiform uniformity of growth. They are fur- 
ther distinguished by the spire never being papillary, and by an important 
change in the disposition of the columellar plaits ; in the Volute the plaits 
enlarge upon the columella as they descend, whilst in the Mitree it is just 
the reverse, for they diminish materially in size as they approximate to 
the base of the shell. There have been one or two attempts to distribute 
the Mitre into smaller genera. De Montford separated the Mitra vulpe- 
cula, and those allied to it, under the generic title of Turris* ; whilst 
Swainson divides the Mitre into no less than five genera, Mitra, Mitreola, 
Mitrella, Tiara and Conoheliz. The last of these, which includes the M:- 
tre dactylus, marmorata, and other short conical forms, had already been 
proposed by Schumacher with the name of Imbricaria, and has been much 
esteemed by conchologists ; the division, nevertheless, exhibits no per- 
manency of character, and cannot easily be maintained. 
Some of the small species of Mitra approximate closely in form and 
general appearance to the Columbelle ; indeed, a few of them were re- 
ferred to that genus by Lamarck ; they may, however, be readily distin- 
guished by remarking the difference already explained between columeilar 
plaits and mere plait-like denticulations (vide p. 216). . 
The shell of Mitra may be described as being elongated, or of an oblong- 
oval form, either turrited, cylindrical, or fusiform, and emarginated at the 
base ; the spire is acuminated, more or less raised, and generally rather 
sharp at the apex; the aperture is narrow, and varies considerably in 
length, sometimes extending but half-way up the shell, and sometimes 
nearly equalling its length; the columella is often recurved towards the 
* We observe another genus besides Turris in Mr. Gray’s ‘Synopsis,’ with the name of 
Vulpecula: surely it must be the same? 
